Microchip Technology 24AA512T-I/SM

Overview

24AA512T-I/SM from Microchip Technology Inc. is a 512 Kbit I²C-compatible serial EEPROM organized as 64K × 8-bit memory, operating from 1.7V to 5.5V with industrial temperature range (–40°C to +85°C), 400 µA max read current, and 1 µA max standby current. It supports page writes up to 128 bytes and hardware write-protection via the WP pin, used in embedded systems for firmware parameter storage and calibration data retention.

For engineers reviewing the 24AA512T-I/SM datasheet, 24AA512T-I/SM pinout, 24AA512T-I/SM application, or 24AA512T-I/SM equivalent, key selection criteria include I²C clock compatibility (up to 400 kHz at V_CC ≥ 2.5V), 128-byte page buffer size, Schmitt-trigger noise immunity on SDA/SCL, and SOIC-8 (SM) package compatibility with standard PCB footprints.

Technical Context

The 24AA512T-I/SM implements a two-wire I²C interface with open-drain SDA/SCL requiring external pull-ups, and uses internal address pointer logic for sequential reads across the full 64K address space. Its cascading capability supports up to eight devices on one bus using A0–A2 chip-select inputs.

Write operations are self-timed with maximum 5 ms byte/page erase/write cycles, and acknowledge polling enables bus efficiency during write completion detection. Hardware write-protection is active when WP = V_CC, disabling all writes while permitting unrestricted reads.

Key Specifications

Pinout & Package

24AA512T-I/SM is supplied in an 8-lead SOIC package (package code SM), measuring 3.9 mm × 4.9 mm × 1.75 mm, with gull-wing leads and JEDEC MS-012AC compliant footprint.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar serial EEPROM applications.

Compared with 24AA512T-I/SM, the 24LC512-I/SM lacks 1.7V operation but matches all other electrical and mechanical specs, while the AT24C512BN-SH-T provides faster clock support and stronger ESD protection at the cost of incompatible packaging and no 1.7V capability.

Availability

24AA512T-I/SM is available at Aetrix Electronics and suitable for industrial sensor calibration, medical device configuration, and automotive body control requiring stable component supply across extended product lifecycles.

Supply support for 24AA512T-I/SM includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Microchip Technology Inc. is a leading provider of microcontrollers, analog components, and memory solutions, headquartered in Chandler, Arizona, with global design and manufacturing operations.

The 24AA512T-I/SM belongs to Microchip's 24XX512 family of I²C serial EEPROMs, designed specifically for low-power, high-reliability nonvolatile data storage in space- and power-constrained embedded systems.

FAQ

What is the maximum I²C clock frequency supported by the 24AA512T-I/SM?

The 24AA512T-I/SM supports up to 400 kHz I²C clock frequency when V_CC is 2.5V or higher. At V_CC between 1.7V and 2.5V, the maximum clock rate drops to 100 kHz. This dual-speed capability ensures interoperability across 1.8V, 3.3V, and 5V systems while maintaining timing compliance per I²C specification. The 24AA512T-I/SM does not support 1 MHz operation - that capability is exclusive to the 24FC512 variant.

Does the 24AA512T-I/SM require external pull-up resistors on SDA and SCL lines?

Yes, the 24AA512T-I/SM requires external pull-up resistors on both SDA and SCL lines because its I/O pins are open-drain. Recommended values are 10 kΩ for 100 kHz operation, 2 kΩ for 400 kHz, and lower values may be needed for higher bus capacitance. These resistors ensure proper signal rise times and bus arbitration; omitting them will cause communication failure. The 24AA512T-I/SM itself contains no internal pull-ups.

How does hardware write-protection work on the 24AA512T-I/SM?

Hardware write-protection on the 24AA512T-I/SM is controlled by the WP pin: when tied to V_CC, all write operations (byte and page) are inhibited while read operations remain fully functional. The WP state is sampled only at the Stop condition of each write command, so toggling WP mid-transaction has no effect. This feature prevents accidental overwrites during power-up/down or firmware errors without requiring software locks. The 24AA512T-I/SM implements this at the silicon level - no internal register configuration is needed.

What is the page write buffer size of the 24AA512T-I/SM, and why does it matter?

The 24AA512T-I/SM features a 128-byte page write buffer, meaning up to 128 bytes can be loaded into the internal latch and written to memory in a single self-timed cycle. This reduces I²C bus transactions by up to 127x compared to byte-wise writes, significantly lowering CPU overhead and bus contention. Because page boundaries align to 128-byte offsets (0x0000–0x007F, etc.), crossing a boundary wraps data within the same page - application firmware must manage address alignment to avoid unintended overwrites. The 24AA512T-I/SM enforces this behavior strictly per its datasheet.

Is the 24AA512T-I/SM RoHS compliant and AEC-Q100 qualified?

The 24AA512T-I/SM is RoHS compliant per EU Directive 2011/65/EU, with lead-free matte tin (Sn) terminations and halogen-free molding compound. However, only the 24AA512 variant (not the T-suffix version) is explicitly listed as AEC-Q100 qualified in Microchip's official documentation. The "T" in 24AA512T-I/SM denotes tape-and-reel packaging; qualification status follows the base part number. For automotive applications requiring AEC-Q100, confirm qualification status via Microchip's official part search or contact their automotive support team before design-in.